Having more problems with my 02 dodge cummins.. wont start
 

My truck wont start when its cold out by its self but my battiers keep dying on me unless it starts right away (after it gets warmed up). Im wondering if this a battery problem or alternator?...or could it be something else. When i jump it with a another truck it starts right up. Any ideas??
Thanks Randy

How cold? do you have it plugged in? I would do a load test on your batteries... they are only good for 5-7 years. low temps= less cranking amps. Always replace batteries in sets.

Call if you need assistance

Check the batteries to see if they are holding a charge and pass a load test. Make sure your connections on both batteries are good. After you determine your batteries and wiring are good check your alternator output.

So found out my batteries were bad now need ideas on what kind of batteries to use. I was thinking either optimas or duralast..
Also thanks for the help

If money was not an object I would run 2 Optima Yellow Tops. As far as stock batteries go, I like Interstate.

What is the least amount of cca should i have?

I wouldnt use a pair of batteries with less than 700 CCA each. Not sure on a spec but off the top of my head, that is what I would go with.